it can provide a source of energy, alcohol (ethanol) does have
metabolic, cardiovascular, thermoregulatory, and neuromuscular actions
that can affect exercise performance. Strength is minimally affected,
and performance impairments depend on the dose of alcohol and subject
habituation to alcohol intake, exercise duration, environmental
conditions, and other factors. Central nervous system function is
impaired at high doses, resulting in decrements in cognitive function
and motor skill, as well as behavioral changes that may have adverse effects on performance.
the universal belief that alcohol consumption in small amounts improves
sports performance, the following ACSM guidelines depict the effects of
alcohol on exercise performance:
- Pychomotor skills impairment
- V02 max is minimally affected
- Acute ingestion is not associated with improvement in exercise capacity and may decrease performance level
- May perturb thermoregulatory mechanisms during exercise, especially in a cold environment.
consumption of alcohol has shown that alcohol myopathy is expressed in
glycolytic muscles, in which protein turnover and glucose metabolism
deficiencies are present. Nonetheless, it is well recognized that
ethanol has a variety of effects on carbohydrate metabolism in skeletal
muscle and liver. Much of the available evidence comes from older
studies using animal models, showing that synthesis of glycogen in both
liver and oxidative skeletal muscle is impaired in the presence of even
relatively low levels of ethanol, though there seems to be no effect on
type 2 muscle fibers. There is also evidence of impaired hepatic
glucose output in the presence of even low doses of ethanol. This may
be of particular concern during prolonged, moderate-intensity exercise
when glucose output from the liver is an important source of energy.
changes are also related to alcohol consumption in moderate to high
doses such as increases in vasopressin, sympathetic nervous system
activity and catecholamine release. Although a complex process,
cardiovascular platelet aggregation is affected by alcohol. Acute
consumption of large amounts is directly related to increased an heart
rate and blood flow. However, these physiological affects are dose
dependent. In addition, temporary declines in left ventricular
contractions and myocardial irritability, which may result in
arrhythmias can be seen.
one of the more significant affects of alcohol is that of immune system
response and host defense. Those who drink regularly and consistently
are more vulnerable to infection with a variety of pathogens and the
ability to ward off infection is weakened. Other immune affects of
alcohol include decreased lymphocyte cell number, impaired macrophage
function and abnormal neutrophil leukocyte adherence.
this gives some brief insight into the physiological and psychological
parameters of alcohol and sports performance, the extent to which this
occurs depends on many factors, including the exercise mode and
duration and the individuals habituation to alcohol intake.
ACSM. (2006). ACSM's Guidelines for Exercise Testing and Prescription
(7th ed.). Philadelphia: Lippincott Williams & Wilkins.
-Sayed MS, Ali N, El-Sayed Ali Z. Interaction between alcohol and
exercise: physiological and haematological implications. Sports Med.
3). Shirreffs SM, Maughan RJ. The effect of alcohol on athletic performance. Curr Sports Med Rep. 2006 Jun;5(4):192-6. Review.
Jonathan Mike, MS, CSCS, USAW, NSCA-CPT, Doctoral Student, Assistant Editor